JP2701648B2 - Engine cooling water control device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cooling water control device for an engine, and more particularly to a control device for controlling the flow of cooling water when the engine is cold.

[0002]

2. Description of the Related Art Conventionally, as a cooling water control device for a water-cooled engine, cooling water whose temperature has increased through a cooling water passage in the engine is cooled by a radiator, and the engine is driven again by an engine driven cooling water pump. There is a forced circulation type that supplies the cooling water to the cooling water passage. This type of device is configured to circulate the cooling water in the engine without flowing to the radiator in a cold state immediately after the start of the engine. A conventional engine cooling water control device will be described with reference to FIG.

FIG. 3 is a block diagram showing a conventional cooling water control device. In the figure, 1 is a water-cooled engine, 2 is a cylinder block of the engine 1, 3 is a cylinder head,
4 is a crankcase. Reference numeral 5 denotes a cooling water passage through which cooling water flows. The cooling water passage 4 is formed in the cylinder block 2 and the cylinder head 3 so as to penetrate through the wall portions thereof. The passage 5a is branched into a plurality of passages, and is collected at a cooling water outlet 5b on the cylinder head 3 side.

Reference numeral 6 denotes a cooling water pump for supplying cooling water to the cooling water passage 5. The cooling water pump 6 has a structure driven by an engine, and has a discharge port provided at an inlet 5a of the cooling water passage 5. And is mounted on the cylinder block 2.

A radiator 7 has a cooling water inlet connected to a cooling water outlet 5b of the engine 1 through a cooling water pipe 7a, and a cooling water outlet connected to the cooling water pipe 7a.
The cooling water pump 6 communicates with the suction port of the cooling water pump 6 via the line b.

The suction port of the cooling water pump 6 is connected not only to the radiator 7 but also to a circulation passage 8 provided in the engine 1. The circulation path 8 has an upstream end communicating with the cooling water outlet 5 b and a downstream end communicating with the suction port of the cooling water pump 6.

The cooling water pipe 7a and the engine 1
Is connected to the cooling water pipe 7a from the cooling water outlet 5b.
A thermo-valve 9 as a thermostat for controlling the amount of cooling water flowing to the air is provided.

When the temperature of the cooling water is lower than the set temperature, the thermo valve 9 closes the cooling water passage connected to the cooling water pipe 7a and opens as the temperature rises.

In the conventional cooling water control device configured as described above, the cooling water pump 6 starts operating when the engine 1 is started, and the cooling water is discharged to the cooling water passage 5 in the engine 1. Immediately after the start of the engine, the thermo valve 9 is closed because the engine temperature and the cooling water temperature are low, and the cooling water collected at the outlet 5b of the cooling water passage 5 is supplied to the radiator 7
Without flowing into the cooling water pump 6 through the circulation passage 8.

That is, when the engine 1 is cold, the cooling water circulates in the engine 1 through the cooling water passage 5 and the circulation passage 8.

The heat generated in the combustion chamber 1a in the engine 1 is transmitted to the cooling water mainly in the vicinity of the cylinder head 3 and the junction between the cylinder head 3 and the cylinder block 2. When the cooling water is circulated in the engine 1, the heat is transmitted to the entire engine 1, and the engine 1 is warmed up.

When the warm-up operation proceeds and the cooling water temperature becomes higher than the set temperature, the thermo valve 9 opens, and the cooling water also flows to the radiator 7. At this time, the cooling water is sucked into the cooling water pump 6 via the radiator 7, and is cooled by the radiator 7.

[0013]

However, in the conventional cooling water control device configured as described above, the combustion chamber 1a
There is a problem that the temperatures of the upper portion of the cylinder block 2 and the cylinder head 3 which affect the combustion state at the time are not stabilized until the warm-up ends. This is because, when the engine 1 is in a cold state, a portion near the combustion chamber 1a is cooled more than necessary by cold cooling water circulating in the engine 1.

That is, when the engine 1 is in a cold state, the combustion state becomes unstable and unburned gas and the like are liable to be discharged. In addition, since the combustion temperature is lowered, the warm-up time is long and the drivability is lowered. Would.

SUMMARY OF THE INVENTION The present invention has been made in order to solve the above-mentioned problems, and provides an engine cooling water control device capable of stabilizing combustion in a cold state of an engine and promoting warm-up. The purpose is to:

[0016]

SUMMARY OF THE INVENTION The cooling water of the engine control system according to the first invention, the discharge port of the cooling water pump, fluid
Fluid inlet of a flow control valve consisting of a three-way valve with two outlets
And one of the fluid outlets is connected to an engine coolant passage.
To the road and the other through a bypass passage.
And a control device for increasing the amount of cooling water flowing toward the engine as the temperature near the combustion chamber of the engine rises, connected to the flow control valve.

A cooling water control device for an engine according to a second invention has two fluid outlets at a discharge port of a cooling water pump.
The fluid inlet of the flow control valve consisting of a three-way valve is communicated,
When one of the fluid outlets is connected to the engine cooling water passage
In both cases, the other is connected to the cooling water pump through a bypass passage.
A control device is connected to the flow control valve, the control device increasing the amount of cooling water flowing to the engine side as the elapsed time from the start of the engine operation becomes longer.

[0018]

When the engine is in a cold state immediately after the start of the engine, the cooling water is returned from the flow control valve to the suction side of the cooling water pump through the bypass passage, and is circulated without passing through the cooling water passage in the engine.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the first invention will be described below in detail with reference to FIG. FIG. 1 is a configuration diagram showing a cooling water control device for an engine according to the first invention. In the same figure, the same or equivalent members as described in FIG.
The same reference numerals are given and detailed description is omitted.

In FIG. 1, reference numeral 11 denotes a flow control valve for controlling the amount of cooling water supplied from the cooling water pump 6 to the cooling water passage 5 of the engine 1. The flow control valve 11 is a three-way valve provided with two fluid outlets. When the opening degree is changed, the flow rate of the fluid flowing out of one of the two fluid outlets is reduced, and the flow rate of the other fluid outlet is reduced accordingly. The structure is such that the flow rate of the fluid flowing out increases. That is, when the flow path connected to one of the fluid outlets is closed, the flow path connected to the other fluid outlet is fully opened. The opening is adjusted by a control device described later.

The flow control valve 11 is mounted on the cooling water pump 6 with the fluid inlet communicating with the discharge port of the cooling water pump 6. One of the two fluid outlets of the flow control valve 11 is connected to a cooling water passage 5 in the engine 1, and the other is a bypass passage 1 provided in the engine 1.
It is connected to 2.

The bypass passage 12 has an upstream end connected to the flow control valve 11 and a downstream end connected to the suction port of the cooling water pump 6 together with the circulation passage 8.

That is, if all the cooling water discharged from the cooling water pump 6 is caused to flow through the bypass passage 12 by the flow control valve 11, it is not supplied to the cooling water passage 5;
As the flow rate in the bypass passage 12 decreases, the supply amount to the cooling water passage 5 increases. And the bypass passage 12
If not, the entire amount of the cooling water discharged from the cooling water pump 6 is supplied to the cooling water passage 5.

Reference numeral 13 denotes a control device for controlling the amount of cooling water supplied to the cooling water passage 5 by changing the opening of the flow control valve 11. The control device 13 is connected to a water temperature sensor 14 attached to the cylinder head 3 and outputs a control signal 16 to the flow control valve 11 in accordance with a temperature signal 15 input from the water temperature sensor 14. It is configured to control the opening degree.

The water temperature sensor 14 is fixed to the cylinder head 3 with a detecting portion (not shown) facing the cooling water passage 5 in the cylinder head 3. The temperature in the cylinder head 3 is determined as the temperature near the combustion chamber 1 a. It is configured to detect the temperature of the cooling water and output a temperature signal 15 corresponding to the temperature of the cooling water to the control device 13.

Then, the controller 13 controls the temperature signal 1
5 is lower than the predetermined temperature, the flow control valve 11 is controlled so that the entire amount of the cooling water flows through the bypass passage 12, and when the detected temperature exceeds the predetermined temperature, The configuration is such that the flow control valve 11 is controlled such that the amount of cooling water supplied to the cooling water passage 5 gradually increases as the detected temperature increases. The control device 13 controls the flow control valve 11 so that the entire amount of the cooling water is supplied to the cooling water passage 5 when the detected temperature is equal to or lower than the temperature at which the thermo valve 9 starts to open. I do.

In the cooling water control device configured as described above, when the engine 1 is in a cold state immediately after the start of the engine, the thermo valve 9 is closed, and the cylinder head 3 is closed.
Since the cooling water temperature is low, the entire amount of the cooling water discharged from the cooling water pump 6 is returned from the flow control valve 11 to the suction port of the cooling water pump 6 through the bypass passage 12. That is, at this time, the cooling water is circulated without passing through the cooling water passage 5 in the engine 1.

As the temperature of the cylinder head 3 increases, the temperature of the cooling water in the cylinder head 3 also increases.
The cooling water temperature is detected by a water temperature sensor 14 and is always input to the control device 13 as a temperature signal 15. Then, when the cooling water temperature exceeds a predetermined temperature, the control device 13 outputs a control signal 16 to the flow control valve 11, and the cooling water discharged from the cooling water pump 6 is also supplied to the cooling water passage 5. The flow control valve 11 is controlled as described above.

When the flow control valve 11 is controlled as described above, the cooling water is circulated in the engine 1 through the cooling water passage 5 and the circulation passage 8, so that the engine 1 is warmed up. Become. Then, as the temperature of the cooling water in the cylinder head 3 increases, the amount of the cooling water supplied to the cooling water passage 5 increases.

After the entire amount of the cooling water discharged from the cooling water pump 6 is supplied to the cooling water passage 5, in other words, after the warm-up operation of the engine 1 is completed, the temperature of the cooling water further decreases. When it rises, the thermo valve 9 opens, and the cooling water flows to the radiator 7 to be cooled.

Therefore, the cooling water is returned from the flow control valve 11 to the suction side of the cooling water pump 6 through the bypass passage 12 when the engine 1 is in a cold state immediately after the start of the engine, and flows through the cooling water passage 5 in the engine 1. It is circulated without. Therefore, it is possible to prevent a portion near the combustion chamber 1a from being cooled more than necessary by the cooling water during the warm-up operation.

Further, when the bypass passage 12 is formed in the engine 1 as shown in this embodiment, the passage pressure loss is reduced and the load on the cooling water pump 6 is reduced, so that the fuel efficiency is improved. Can be.

In this embodiment, an example has been shown in which the temperature of the cooling water of the cylinder head 3 is detected in detecting the temperature in the vicinity of the combustion chamber 1a. However, the present invention is not limited to such a limitation. Alternatively, the temperature of the cooling water in the upper part of the cylinder block 2 may be detected, or the temperature of the cylinder head 3 itself or the temperature of the cylinder block 2 itself may be detected.

Further, the control device 13 shown in this embodiment is
The configuration is such that the coolant is not supplied to the coolant passage 5 until the coolant temperature detected by the coolant temperature sensor 14 reaches the set temperature. It is also possible to adopt a configuration in which the supply flow rate to the cooling water passage 5 is simply increased as the temperature of the cooling water increases.

Next, an engine cooling water control apparatus according to the second invention will be described in detail with reference to FIG. FIG. 2 is a configuration diagram showing an engine cooling water control device according to a second invention.
In this figure, the same or equivalent members as those described in FIG. 1 are denoted by the same reference numerals, and detailed description is omitted.

In FIG. 2, reference numeral 21 denotes a timer. The timer 21 starts measuring the time when the engine 1 starts operating, and outputs the elapsed time from the start of the engine operation to the control device 22. I have.

The control device 22 is configured to control the amount of cooling water flowing from the flow control valve 11 to the cooling water passage 5 according to a function based on the elapsed time. More specifically, the cooling water does not flow to the cooling water passage 5 until a certain time has elapsed from the start of the engine operation, and after the certain time has elapsed, the cooling water becomes longer as the time elapsed from the start of the engine operation becomes longer. It is configured to increase the amount of water supplied to the passage 5.

With this configuration, when the engine 1 is in a cold state immediately after the start of the engine, the cooling water is returned from the flow control valve 11 to the suction side of the cooling water pump 6 through the bypass passage 12, and It is circulated without passing through the cooling water passage 5. Therefore, it is possible to prevent the portion near the combustion chamber 1a from being cooled more than necessary by the cooling water during the warm-up operation.

In this embodiment, an example has been described in which the cooling water is not supplied to the cooling water passage 5 until a certain time has elapsed after the engine is started. However, the control is performed without waiting for a certain time after the engine is started. Alternatively, control can be performed so that the amount of water supplied to the cooling water passage 5 is immediately increased.

[0040]

Cooling water control apparatus for an engine according to the first invention described above, according to the present invention is the discharge port of the cooling water pump,
Flow control valve fluid consisting of a three-way valve with two fluid outlets
Connect the inlet to one of the fluid outlets to cool the engine
While communicating with the water passage, the other
A control device for increasing the amount of cooling water flowing to the engine side as the temperature in the vicinity of the combustion chamber of the engine increases, the control device being connected to the suction port of the cooling water pump through the flow control valve; An engine cooling water control device according to a second aspect of the present invention provides a cooling water pump having a fluid outlet at a discharge port thereof.
Flow control valve consisting of a three-way valve with two
Through one of the fluid outlets to the engine coolant passage.
And the other is
Since the control device is connected to the suction port of the cooling water pump and the flow control valve is connected to a control device that increases the amount of cooling water flowing to the engine side as the elapsed time from the start of the engine operation increases. The cooling water is returned from the flow control valve to the suction side of the cooling water pump through the bypass passage and circulated without passing through the cooling water passage in the engine when the engine is in a cold state immediately after the start of the engine.

Therefore, the portion near the combustion chamber can be prevented from being cooled more than necessary by the cooling water during the warm-up operation, so that the upper part of the cylinder block and the cylinder head which affect the combustion state in the combustion chamber can be prevented. Will quickly stabilize.

For this reason, even when the engine is cold, the combustion state is stable and unburned gas and the like are hardly discharged.
The combustion temperature is relatively high, which can promote warm-up.

Further, according to the present invention, since the configuration is adopted in which the circulation amount of the cooling water of the engine is controlled by the flow control valve, the apparatus can be manufactured at low cost and with high accuracy.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing a cooling water control device for an engine according to a first invention.

FIG. 2 is a configuration diagram showing an engine cooling water control device according to a second invention.

FIG. 3 is a configuration diagram showing a conventional cooling water control device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Engine 2 Cylinder block 3 Cylinder head 5 Cooling water passage 6 Cooling water pump 7 Radiator 8 Circulation passage 9 Thermo valve 11 Flow control valve 12 Bypass passage 13 Controller 14 Water temperature sensor 21 Timer 22 Controller

Claims (2)

(57) [Claims] An engine cooling water control device including an engine-driven cooling water pump and a thermostat for circulating cooling water in the engine without passing through the radiator, between the cooling water passage and the radiator of the engine. In the three-way valve having two fluid outlets at the outlet of the cooling water pump
The fluid inlet of the flow control valve consisting of
One of the ports is connected to the engine coolant passage
The other is connected to the cooling water pump through a bypass passage.
An engine cooling water control device connected to the suction port and connected to the flow control valve, the control device increasing the amount of cooling water flowing to the engine side as the temperature near the combustion chamber of the engine increases. . 2. An engine cooling water control device including an engine-driven cooling water pump and a thermostat for circulating cooling water in the engine without passing through the radiator, between the engine cooling water passage and the radiator. In the three-way valve having two fluid outlets at the outlet of the cooling water pump
The fluid inlet of the flow control valve consisting of
One of the ports is connected to the engine coolant passage
The other is connected to the cooling water pump through a bypass passage.
An engine cooling water control, characterized in that a control device for increasing the amount of cooling water flowing to the engine side as the elapsed time from the start of the engine operation becomes longer is connected to the flow control valve in communication with the suction port. apparatus.